a new battery was installed by a mechanic who said my car would not crank bc it had poor cold cranking amps, well it worked for a while. Two weeks later, or today, the problem has occured again. I dont want to spend too much unnecessary money...any advice. The problem is when I turn the car over it just loads the intake and will not crank and then sputters a bit after trying to start it, identical to what it did b4 the battery swap, which temporarily fixed the problem...now the battery is fine and it is doing the same thing...it has not been tuned up since my brother bought it about a year ago...and it is about 400 miles past due an oil change....However I am trying to figure out the best way to get to and identify the ICM, optispark, or any other spark related items...as well as how to expose them so that I can replace them if they turn out to be bad....any advice please respond....im on a budget and now stranded....

 

It's hard to understand completely if you have a cranking problem as apposed to a starting (firing) problem.

Let's assume you have a cranking problem in which the starter rotates slowly. A new battery can mask a few different problems. Remember it takes a certain amount of current to properly rotate the starter. Certainly a weak/ old battery could be the problem. So can temperature. Poor connection quality and a defective starter can also give you the same symptoms.

If for example you have a poor connection. It requires more current to overcome the resistance of a poor connection. A battery that is older, may have too much internal resistance to be able to supply enough current to over come the resistance of the poor connection. Put a new battery in and for a while it will crank the starter fine. However, the poor connection if left unrepaired, will reduce the amount of current put back into the battery from the alternator. Over time, the new battery is reduced in it's ability to crank the starter properly and it too becomes weak.

If a connection were the problem or the alternator were the problem, the mechanic could have easily diagnosed it right after having replaced the battery. All he need have done would have been to check the voltage across the battery once the engine is running to be sure it is around 14 volts.

Therefore it is a good idea to remove several connections, actually clean the connectors and the contact points with a wire brush and then retighten them. They are: Connections at the battery (obviously), at the passenger fender,(both positive clusters and negative clusters), at the alternator and last, the ground strap from the frame to the engine on the driver side.

The other cause for your problem could be either a defective alternator or starter. If the alternator were a problem, it would not charge the battery back to full potential and over time the battery gets weaker and weaker. Again, test it by checking the voltage across the battery while the engine is running.

The last cause of your symptoms could be a starter that is going bad but hasn't got there yet. Internal shorting of the windings causes a starter to pull more current. At some point, the required current will be too much for a battery as it ages or gets colder (you should say where you live) as cold reduces the output of a battery proportionate to the temperature drop. Measure across the battery but this time while someone is cranking the starter. The voltage across the battery should not be less than about 11 volts give or take.

Since you have the same symptom a while later after having replaced the battery, I'de say first choice wiring, second choice alternator, last choice starter. Remember one simple measurement across the battery is all it takes to find out.

good luck.

 

there are easy ways to check for spark.... assuming the car will crank over just fine at the normal cranking speed.
1) crank the car over and watch your tach. if the tach moves, then you have a secondary ignition problem. if the tach does does not move at all, then you have a primary ignition problem. the primary ignition systems consists of all ignition components that recieve 12v from the battery and or alternator. the coil, icm, optispark input, etc are primary components. secondary components are the spark plugs, wires, and secondary side of the coil.

2) get a spark tester from the auto parts store. pull off a plug wire and place it in the boot. ground it and then crank. this will tell you if you are getting spark to the secondary side of the system.

I don't think it's a spark problem since it starts. sounds more like the wiring/grounds to the starter have high resistance. this would cause it to crank slowly and require a lot of battery power to start the car. test this by using jumped cables and another car. try to jump start it. this would supply more than enough current to start the car.

 

Dumb luck that I did this...but sensing it was battery issues I jumped it off and still got no luck the tach does sit still while I try to turn it over which it why i think it is firing issues...however I held the ignition for more than 5 seconds and something toward the front of the motor sounded like <cold water dripping on a hot stove eye> when it fried and white smoke blew from under the hood for about 10 seconds. It was a blue/white haze with not much of an odor....Ive heard what it may be but Im unsure of the process of how to narrow it down without having to tear the whole front of my car apart